Early life stage is a term used to describe the developmental stages of an organism before it reaches maturity. The two most common early life stages are LARVA and EMBRYO. LARVA is a stage in the life cycle of an insect or other invertebrate animal, typically characterized by a distinct body form and the absence of wings. EMBRYO is the early stage of development in animals and plants, consisting of a single cell or a cluster of cells from which a complete organism develops.